Process and device for cutting glass panes

ABSTRACT

When the glass pane ( 3 ) is cut with a water jet which is pointed against the glass pane ( 3 ) from a nozzle ( 7 ) with high pressure, a water surge is directed at the glass pane ( 3 ) on the side opposite the action site of the cutting water jet to a point which is opposite the nozzle ( 7 ). The water jet which is cutting the glass pane ( 3 ) is captured damped by the water surge without its atomizing and rebounding onto the back of the glass pane ( 3 ).

[0001] The invention relates to a process for cutting glass panes using a pressurized water jet which is pointed at the glass pane and to which an abrasive material is optionally added.

[0002] It is known that glass panes can be cut using a water jet which with a pressure of roughly 3000 bar from a nozzle is pointed at the glass pane to be cut. The known cutting of glass panes with a water jet is done with the glass panes placed horizontally, underneath the glass pane there being a water bed with a surface which is located under the glass pane at a distance. In the water bed there are supports which project over the water surface and on which the glass pane rests. In the known cutting of glass panes the water jet is moved along the stipulated cutting outline with the glass pane stationary.

[0003] It is a problem in the known process that the water jet inevitably hits the supports now and then, rebounds from them and thus the water jet and the abrasive material contained in it damage the bottom of the glass pane with the result that there are dulled sites in the glass.

[0004] To solve this problem it has already been proposed that a foam layer be inserted between the glass pane and the supports. This approach is a problem in that the foam layer must be renewed each time and it crumbles under the action of the water jet, therefore is broken into small parts so that major fouling problems arise.

[0005] In the known process for cutting glass panes with a water jet it is also a problem that when the water jet hits a support the water is uncontrollably atomized and furthermore considerable noise develops.

[0006] The object of the invention is to devise a process for cutting glass panes with a water jet which solves these problems and which can be carried out especially without the known foam layer.

[0007] As claimed in the invention this object is achieved with a process with the features of claim 1.

[0008] Preferred and advantageous embodiments of the invention are the subject matter of the claims dependent on the main process claim.

[0009] The invention extends to a device for executing the process as claimed in the invention, which device is characterized by the features of the main equipment claim.

[0010] Preferred and advantageous embodiments of the device as claimed in the invention are the subject matter of the dependent claims which depend on the main equipment claim.

[0011] In the process as claimed in the invention it is precluded in any case that the water jet with which the glass pane is cut strikes (rigid) supports since the water jet which cuts the glass pane on the back (=the side opposite the side on which the water jet acts) of the glass pane is captured by the water surge pointed at the back of the glass pane. In this way, unwanted rebound phenomena and the resulting dulled sites on the glass pane are reliably prevented. Furthermore, the process as claimed in the invention yields the advantage that the noise development when cutting the glass panes with a water jet is greatly reduced. The process as claimed in the invention also offers the advantage that the water beds which are necessary in the known process for cutting glass panes with a water jet are dispensable so that the equipment and operating engineering costs are kept within limits.

[0012] Preferably the process as claimed in the invention is carried out with the glass panes aligned roughly vertically.

[0013] Other details and features of the invention result from the following description of one example of the process of the invention with reference to one sample embodiment of a device as claimed in the invention suitable for carrying out the process of the invention, using the drawings.

[0014]FIG. 1 schematically shows in a front view a device for cutting glass panes with a water jet and

[0015]FIG. 2 shows a side view thereof.

[0016] The device as claimed in the invention comprises a support wall 1 which is made as a slide surface (for example a roller bay or air cushion support wall) and which is aligned essentially vertically and is tilted to the rear preferably by a few degrees, for example by 5°, so that a glass pane 3 which stands on a conveyor means 2 (for example a roller conveyor) on the lower edge of the support wall 1 leans against the latter. In the support wall 1 there is a vertical slotted interruption 4 (gap) which preferably passes over the entire height of the support wall 1.

[0017] In front of the support wall 1 there is a guide rail 5 on which a carriage 6 is guided adjustably up and down and which bears a water jet nozzle 7. To move the carriage 6 and thus the water jet nozzle 7 along the guide rail 5, therefore essentially vertically up and down, there are conventional drives for the carriage 6, as for example a toothed belt drive, a spindle drive, a spindle nut drive or a rack and pinion drive (not shown).

[0018] Behind the support wall 5 there is likewise a guide rail 10 on which a carriage 11 is guided to be able to move up and down. There is also a drive, for example one of the aforementioned drives, for the adjustment of this carriage 11.

[0019] The carriage 11 bears a hollow chamber 12 with an opening 13 which is pointed at the slotted interruption 4 in the support wall 1. A line 14 is connected to the hollow chamber 12 and from a water tank 15, using a pump 16, optionally via a filter 17, the line routes water into the chamber 12 and the water surges out of the opening 13 of the chamber 12.

[0020] The drives of the carriage 6 for the water jet nozzle 7 on the one hand and the carriage 11 for the hollow chamber 12 on the other are synchronized with one another so that the carriages 6 and 11 moved up and down synchronously along their guide rails 5 and 10 and the opening 13 is aligned in the hollow chamber 12 always opposite the water jet nozzle 7. Thus, the water jet nozzle 7 is pointed from the front at the glass pane 3 and the opening 13 of the hollow chamber 12 is always located concentrically to the axis of the water jet nozzle 7 on the other side (the back) of the glass pane 3.

[0021] To simplify synchronization of the movements of the water jet nozzle 7 and the chamber 12 the drives for the carriages 6 and 11 can be coupled to a common drive motor.

[0022] The conveyor means 2 on the lower edge of the support wall 1 is aligned for example as a roller conveyor and is coupled to the drive. The conveyor means 2 can also be a (toothed) belt conveyor.

[0023] When the glass pane 3 is being cut, the water jet nozzle 7 and the hollow chamber 12 with the opening 13 for the water surge pointed at the back of the glass pane 3 are moved simultaneously with it and synchronously up and down, as is illustrated by the arrows 20 in FIGS. 1 and 2. When cuts deviating from the vertical direction are to be produced in the glass pane 3, it is moved using the conveyor means 2 horizontally along the support wall 1. Also combined movements of the water jet nozzle 7 and the glass pane 3 can be carried out in order to be able to cut along any cutting outlines.

[0024] To ensure reliable, controlled and accurate movement of the glass pane 3, above the conveyor means 2 there can be driving means 30 (tugging means) which engages preferably the front side of the glass pane 3. In one simple embodiment this driving means 30 is equipped with a vacuum-pressurized suction head 31 which can be moved along the guide rail 32 and which is applied to the glass pane 3 and provides for reliable and accurate transport of the glass pane 3 in the horizontal direction along the support wall 1.

[0025] The tank 15 from which water is routed to the hollow chamber 12 can be used at the same time as a collecting trough for the water emerging from the water jet nozzle 7 and is therefore preferably arranged such that the water running down from the action site of the water jet emerging from the nozzle 7 and the water emerging from the opening 13 of the hollow chamber 12 are captured by the tank 15 which is made as a trough open to the top.

[0026] The pressure with which the hollow chamber 12 is supplied with water is such that from its opening 13 surging water makes contact with the back of the glass pane 3 at a point which is opposite the action site of the water jet emerging from the water jet nozzle 7. This effectively prevents the water jet emerging from the water jet nozzle 7 after passing through the glass pane 3 from striking a hard resistance (rebounding), but rather is captured damped by the water surge and therefore is not atomized. Thus, on the one hand damage to the back of the glass pane 3 is prevented and the noise which develops in the operation of the device as claimed in the invention for cutting glass panes according to the process of the invention is kept within limits.

[0027] In addition, the noise development can be limited when the hollow chamber 12 is accommodated in a housing 40 (shown by the broken line in FIG. 2) of noise-damping material, the walls of the housing 40 projecting into the immediate vicinity of the back of the glass pane 3 and only its lower wall of the housing 40 having a distance from the glass pane 3 in order to allow the water to flow out into the collecting trough 15.

[0028] In the process and device for cutting glass panes 3 with a water jet as has been described previously, it is a major advantage that the water jet which cuts the glass pane 3 after its passage through the glass pane 3 is captured by the water surge pointed at the back of the glass pane 3 such that rebound of the water mixed with the abrasive onto the glass pane 3 is reliably prevented.

[0029] In summary one preferred example of the invention can be described as follows.

[0030] When the glass pane 3 is cut with a water jet which is pointed against the glass pane 3 from a nozzle 7 with high pressure, a water surge is directed at the glass pane 3 on the side opposite the action site of the cutting water jet to a point which is opposite the nozzle 7. The water jet which is cutting the glass pane 3 is captured damped by the water surge without its atomizing and rebounding onto the back of the glass pane 3. 

1. Process for cutting a glass pane with a water jet, an abrasive material being optionally added to the water jet and the water jet being pointed at the glass pane to be cut, characterized in that a water surge is directed to the side of the glass pane which is opposite the side thereof at which the cutting water jet is directed and the water surge touches the glass pane at a site which is opposite the action site of the cutting water jet on the glass pane.
 2. Process as claimed in claim 1 , wherein the glass pane to be cut is aligned essentially vertically.
 3. Process as claimed in claim 1 or 2 , wherein between the glass pane to be cut on the one hand and the water surge and the water jet which cuts the glass pane on the other relative motion which corresponds to the cutting outline is executed.
 4. Process as claimed in one of claims 1 to 3 , wherein the water jet which cuts the glass pane and the water surge which is directed at the glass pane in the course of cutting are moved in a first direction and the glass pane is moved in a second direction which is perpendicular to the first direction.
 5. Process as claimed in claim 4 , wherein the water jet which cuts the glass pane and the water surge which is directed at the glass pane are moved horizontally in a vertical plane and the glass pane is moved horizontally.
 6. Process as claimed in one of claims 1 to 5 , wherein the water of the water jet and of the water surge running down from the cutting site is collected and used to form the water surge.
 7. Process as claimed in claim 6 , wherein the water used to form the water surge is filtered to remove abrasive material.
 8. Device for executing the process as claimed in one of claims 1 to 7 , with a nozzle (7) for producing the water jet which cuts the glass pane (3), with a means for feeding pressurized water to the nozzle (7) and with a means for producing relative motion between the nozzle (7) and the glass pane (3) to be cut, wherein a support wall (1) which is made as a sliding surface is provided with a conveyor means (2) which is provided on the lower edge of the support wall (1) for the glass pane (3), wherein the nozzle (7) can be moved on a carriage (6) on a guide (5) along the support wall (1), wherein in the support wall (1) opposite the nozzle (7) there is an interruption (4) in the form of a slot which is aligned parallel to the guide (5) in a vertical plane, wherein a chamber (12) with an opening (13) opposite the nozzle (7) for emergence of a water surge is assigned to the side of the glass pane (3) opposite the nozzle (7) and wherein the chamber (12) can be moved synchronously with the nozzle (7).
 9. Device as claimed in claim 8 , wherein the nozzle (7) is located on a carriage (6), wherein the carriage (6) can be adjusted along a guide rail (5) and wherein the guide rail (5) is aligned parallel to the support wall (1) and to the interruption (4) in it.
 10. Device as claimed in claim 8 or 9 , wherein the chamber (12) is located on a carriage (11), wherein the carriage (11) can be adjusted along the guide rail (10) and wherein the guide rail (10) is aligned parallel to the support wall (1) and to the interruption (4) in it.
 11. Device as claimed in claim 9 and 10 , wherein adjustment means are assigned to the carriages (6, 11) for the nozzle (7) and the hollow chamber (12).
 12. Device as claimed in claim 11 , wherein the adjustment means for the carriages (6 and 11) are coupled to a common drive motor.
 13. Device as claimed in one of claims 8 to 12 , wherein the support wall (1) is tilted to the rear by a few degrees, preferably by 5°.
 14. Device as claimed in claim 13 , wherein the interruption (4) is made as a slot which is aligned in the vertical plane and which passes essentially the entire height of the support wall (1).
 15. Device as claimed in one of claims 9 to 14 , wherein the guide rails (5 and 10) are aligned according to vertical planes.
 16. Device as claimed in one of claims 8 to 15 , wherein a tugging means (30) which engages the glass pane (3) is assigned to the conveyor means (2) for moving the glass pane (3) along the support wall (1).
 17. Device as claimed in claim 16 , wherein the tugging means (30) has at least one vacuum-pressurized suction head (31) which can be placed against the glass pane (3).
 18. Device as claimed in one of claims 8 to 17 , wherein underneath the support wall (1) is a tank (15) which is made as a trough which is open to the top.
 19. Device as claimed in claim 18 , wherein a line (14) which is supplied with water is connected to the chamber (12).
 20. Device as claimed in claim 19 , wherein the line (14) proceeds from the tank (15).
 21. Device as claimed in claim 19 or 20 , wherein there is a filter (17) in the line (14).
 22. Device as claimed in one of claims 8 to 21 , wherein the chamber (12) is surrounded with a housing (40) of noise-damping material.
 23. Device as claimed in claim 22 , wherein the walls of the housing (40) which are essentially perpendicular to the glass pane (3) except for the lower wall extend directly to the glass pane (3).
 24. Device for cutting a glass pane with a water jet, comprising means for directing a cutting water jet against one side of a glass pane to cut the glass pane, and means providing a water surge against the side of the glass pane which is opposite the side thereof against which the cutting water jet is directed. 